Mercury electric lamp



Sept. 15, 1925.

R. L. M BELLEAUD ET AL MERCURY ELECTRIC LAMP Filed Dec. 1920 2 Sheets-Sheet 1 I Jruem /m "7s; e'fwmm- M192 zzmwz W 1 01419 fg k ,7,

R. L. M. BELLEAUD ET AL Sept. 15. 1925.

MERCURY ELEGTRI C LAMP 2 Sheets-Sheet 2 Filed Dec. 16, 1920 Eff . tween the electrodes.

Patented Sept. 15, 1925.

UNITED STATES PATENT OFFICE.

RENE LOUTS MAXINE BELLEAUD AND JEAN BARROLLIER, OF COURBEVOIE, FRANCE.

MERCURY ELECTRIC LAMP.

Application filed December 16, 1920. Serial No. 431,104.

'1 '0 all whom it may] concern-.-

Be it known that we, Rani Louis Maxim: Bennmun flIRl JEAN BARROLLIER, both citizens of the Republic of France, both residing at Com-heroic, Seine, France, have invented certain new and useful lmprovements in Mercury Electric Lamps, of which the following is a specification.

The majority of mercury vapor lamps heretofore constructed present various defects. 1n the operation of the lamp there occurs a transfer ol mercury from the anode to the cathode. This is due mainly to the anode being at a higher temperature than the cathode so that the mercury distils from the anode towards the cathode. Moreover, by reason of the difference of temperature between the anode and the cathode, it sometimes happens that the anode is subjected to excessive heating, whilst the cathode is at a temperature too low to permit a sufficient vaporization of the mercury and a high output from the lamp in visible and ultra-violet radiations. In fact, if the cathode is too cool, the result is a general cooling of the arc, and it is well known that the smaller its heat the poorer it is in ultraviolet radiations.

These several detects result from the difference in temperature between the points of the anode and of the cathode from which the electric arc is formed.

Our present invention consists in an improved mercury or amalgam vapor lamp, in which the temperatures between the anode and the cathode are equalized, permitting the lamp to be operated under high voltage, without an appreciable transfer of mercury from the anode to the cathode occurring and without any of the components of the lamp being raised to a temperature liable to alter such conditions.

Our improved lamp has a mass composed of a certain variety of substances, conductors of heat and separate from the mercury or amalgam constituting the electrodes, the said mass surrounding such electrodes, preferably in the immediate neighbourl'iood of the point from which the arc is generated, thereby ensuring an interchange of heat be- This mass thus constitutes an equalizer of temperature between the two electrodes. Moreover, the said mass stores up a certain amount of heat and therefore serves as a regulator or balancer cathode.

Embodiments of the lamp in accordance with our. invention are shown, by way of example, on the annexed drawing, on which Fig. l is a longitudinalsection through a lamp; Fig. 2, a perspective View of a set of two such lamps; Figs. 3-5 illustrate various other embodiments of our invention.

'lheilluminating tube 1, in which the arc plays, is bent in such a manner thatthe points of starting and arrival of the are at the electrodes 2 and 3 are in proximity to one another.

A container 4 is welded around the'electrodes. This container is partially filled by a substance or a mixture of substances 5, conductors of heat, e, g. mercury, or any other suitable conductor of heat. This substance isintroduced by a neck 6 which is afterwards sealed.

The substance 5 thus serves as a temperature regulator and temperature equalizer between the two electrodes. 1

A similar container such as 4, may be common to several mercury lamps as shown in Fig. 2 wherein is shown a set of two mercury lamps 1, which have a common container 4.

The container 4: may assume any suitable shape, and the mass 5 therein may be any suitable substance or mixture of substances. The only requisite is that the mass possess a certain calorific conductivity enveloping the two electrodes and ensuring a suflicient interchange of heat between them. Thus, instead of arranging a container 4 common to the two electrodes, two separate containers 7, 8 (Fig. 3) can be provided each surrounding an electrode 2, 3 but interconnected by connectors of good heatconducting material, such as metal rods 9, good heat conducting liquid, etc. Also, the mass may consist ofa series of Wires 10 (Fig. 4) or a metal envelope, enclosed as a core or not inany suitable kind of matrix '11, or even of a mass of quartz or porcelain 12 (Fig. 5) uniting the electrodes.

Our invention thus enables the generation of intensive arcs of high output, with out material transfer of mercury from the anode to the cathode, the lamps being of simple construction, compact dimensions and great durability, as none of the parts is raised to an excessive temperature. I.

And-these lamps can have anodes and cathodes which are alike, which simplifies their construction and use.

\Ve claim as our invention:

1. In a metal vapor lamp, the combination with the illuminating tube and the spaced electrodes, of a heat conductive reguspaced electrodes,

lating mass secured to and surrounding the said electrodes.

2. A metal vapor lamp as specified in in claim 1, in which the said regulating mass surrounds the electrodes in the immediate vicinity of the points of-departure and arrival of the arc,

3. In a metal vapor lamp, the combination with the ill'uminatin tube and the the electrodes and secured thereto forming a unitary structure therewith, and a mass of heat conducting material in said casing constantly maintaining the electrodes at equal temperatures. In testimony whereof we have affixed our signatures.

RENE LOUIS MAXIME BELLEAUD.

p JEAN BARROLLIER.

of a casing surrounding 

